1. Field of the Invention
The present invention relates to a flexible hose which has proper flexibility and strength despite an air-permeable structure and, more particularly, to a flexible hose which can be suitably used in a vacuum cleaner as a suction hose for connecting a suction nozzle to a cleaner body.
2. Related Art
In a flexible hose to be used as a sucking/discharging or blowing duct, a portion of air to pass through the hose may have to be discharged to an exterior of the hose from a midway portion of the hose, or may have to be sucked in from the exterior of the hose from this midway portion. For example, when an electric conductor is inserted into the hose, heat generation of the electric conductor can be suppressed by introducing cooling air into the hose. At this time, cooling efficiency can be further improved by introducing fresh air through individual portions of the hose, in a hose longitudinal direction, from exterior of the hose.
Alternatively, an entrance of a hose can be disposed to face hot air exiting from a warming fan heater to introduce the hot air into the hose and to blow the hot air from a midway air-permeable portion. Accordingly, it is conceivable to utilize this hose for drying wash, or to utilize the hose as a steamer by disposing a wet cloth at the air-permeable portion.
However, such a flexible hose is provided with an air port such that it is defective in that strength of the hose is reduced, and a shape keeping property of the hose is also reduced.
With regard to a home vacuum cleaner, generally, a cleaner body having a suction motor and a filter therein is connected with a suction nozzle, having a suction port, through a flexible cleaner hose so that dust sucked from the suction port of the nozzle is fed from the cleaner hose to, and collected in, the cleaner body while air having passed through the filter in the cleaner body is discharged from an exit port in the cleaner body to an exterior of the cleaner body.
When air is thus discharged from the cleaner body, however, recognized have been disadvantages in that dust is blown upwardly, by discharge pressure, from a floor, and that air exiting the exit port has an unpleasant odor.
In order to solve these problems, there has been developed in recent years a cleaner hose having a double tube structure. In this structure, air having passed through the filter is not discharged as it is to exterior of the cleaner body, but is rather circulated from one passage of the cleaner hose to the nozzle, and having left the nozzle is sucked again as sucking air from the suction port, so that a kind of circulation circuit is constructed.
If the sucked air is not completely discharged, but rather wholly suppliedd to the nozzle, load on a suction motor is so seriously increased by passage resistance up to the nozzle that calorific power is increased. If capacity of the suction motor is enlarged to counteract this, the vacuum cleaner is defective because of its enlarged size and increased costs related to the enlarged suction motor.
If the cleaner hose includes an inner tube and an outer tube, clearance between the inner tube and the outer tube is not so large that these tubes are prevented from rubbing against each other when the hose is bent. As this rubbing is repeated, the hose may be worn and thinned so much as to be broken. Specifically, if in one of the inner tube and the outer tube there are sheathed conductors for connecting the vacuum cleaner body to a switch or the like on the nozzle side, these conductors may be exposed as the aforementioned wear proceeds.
Therefore, a first object of the invention is to provide a flexible hose which has a sufficient strength while retaining air-permeability.
Another object of the invention is to provide a flexible hose, which is formed by helically winding both a resin tape and an air-permeable tape, so that a desired length of the hose from short to very long can be arbitrarily provided.
Still another object of the invention is to provide an optimum hose in which a resin tape of a soft resin is reinforced by a reinforcing core, or cores, so that the hose is provided with additional and proper flexibility and strength, and is optimized so as to be capable of being repeatedly bent.
A further object of the invention is to provide a flexible hose which is formed by helically winding an air-permeable tape, reinforced by a reinforcing core or cores, so that the hose is provided with a strength and a proper flexibility throughout its entirety while retaining a sufficient air-permeability over its entirety.
A further object of the invention is to provide a cleaner hose for releasing a portion of hot air to be circulated to a nozzle, which cleaner hose has suitable flexibility and strength while retaining an air-permeability.
A further object of the invention is to provide a hose which is formed by helically winding soft resin tape integrally with an air-permeable tape sandwiched between end edge portions of the soft resin tape in a hose longitudinal direction so that hose strength and proper flexibility are provided throughout the hose in its entirety via a shape keeping property and flexibility of the soft resin tape, while air-permeability of the hose is retained, such that the hose is optimized as an outer tube of a cleaner hose having a double-tube structure.
A further object of the invention is to provide a flexible hose for a cleaner, which hose can release a portion of hot air circulating toward a nozzle through an air-permeable portion of an outer tube of the hose, so that the hose can prevent a motor of the cleaner body from being overheated, to thereby improve durability of the motor.
A further object of the invention is to provide a flexible hose to be used as a cleaner hose, which hose can easily be enabled to have an arbitrary draft by changing a ratio of widths of an air-permeable tape and a resin tape which are to be helically wound on each other.
A further object of the invention is to provide a flexible hose to be used as a cleaner hose, in which an air-permeable tape is a two-layered structure of a woven fabric and a non-woven fabric so that weaving members of the woven fabric, especially in a hose longitudinal direction, resists tension in the longitudinal direction when the hose is bent, while dust in the hose is prevented by the non-woven fabric from being discharged together with a heated discharge, whereby a strong hose can be obtained.
A further object of the invention is to continue an air-permeable effect for a long time by winding a woven fabric on an outer side of a hose while preventing air-permeable holes of the woven fabric, via a filter effect of the non-woven fabric, from being clogged by dust.
A further object of the invention is to provide a flexible hose for a cleaner, in which an air-permeable tape and a resin tape are fused with a reinforcing resin core, or cores, of the resin tape so that a highly strong fusion is obtained via high heat capacity of the reinforcing core, or cores, to reduce separation at fused portions.
A further object of the invention is to provide a double-tube structure having an inner tube and an outer tube, which can reduce wear of a cleaner hose, as might otherwise occur due to rubbing between the inner tube and the outer tube when frequently bent, by providing lubricating properties, via a lubricant, to at least one of an outer circumference of the inner tube and an inner circumference of the outer tube that may possibly rub against each other.